O this is ridiculous.

Ok I have a video clip on the timeline. Everytime I want to import another video clip, it keeps crashing (not responding). This only happens when I want to import another video while I already have a video on the project timeline.

Me too. I've never had a crash. The worst I've ever had to put up with is (and this is only on my laptop) slowish response times rendering and semi jerky preview.

TW - When did this start happening and was it after you installed something else? Perhaps an XP system restore might help? (I don't think it's a 'bug' either.... Vegas, as Mark says is usually very stable indeed)